The present invention relates to document endorsers and more particularly to endorser assemblies of modular design and endorser drums therefore which provide for printing of wide "stripes" of graphic data while preventing "back printing."
The present invention relates to printing devices and more particularly to a novel rotatable print drum for printing variable data on paper documents at a relatively high speed as the documents pass through the printing location and wherein the print drum is provided with resilient self-aligning print wheels for printing variable data, and resilient inserts for printing semi-permanent data.
A large variety of paper document handling and counting devices are presently available in the marketplace and preferably have a capability of counting and stacking paper such as tickets, food coupons, bank notes, checks, and the like. The most desirable paper handling and counting devices preferably have the capability of accurately counting documents at high operating speeds.
In addition to the requirements of counting and stacking documents at high speeds, many applications require a printing, cancelling, or endorsing capability in which fixed data is imprinted upon each paper document as it undergoes a handling and counting operation, the printing being performed by means of a rotating endorser drum having data-bearing surfaces arranged at predetermined locations around the periphery of the drum and adapted to rollingly engage an ink transfer roll and to engage the paper documents passing through the printing location and thereby transfer an ink pattern to the paper. Many such applications further require that variable data be printed on only one surface of each paper document. The printing operation must be also capable of being performed without in any way affecting (i.e., reducing) the high speed operation of the paper handling and counting machine.
For applications in which "back printing" is to be avoided, it is typical to employ a platen or backing roll having grooves aligned with the raised resilient portions of the endorser drum bearing the printed matter. The spatial relationship between the printing surfaces of the endorser and the aligned grooves is such that these confronting surfaces should not come into contact with one another at the time that the endorser drum is in the "engaged" position and when no paper is passing therebetween. Thus the portion of the document which is printed upon when passing between the platen and the endorsing drum is substantially unsupported by the platen roller. As a result, the width of the raised printing surface (measured in the axial direction of the endorser drum) containing the fixed or variable data is severely limited since, it has been found that when the raised portion containing the graphic matter to be printed is made too wide, the cooperating groove in the platen roll must be made at least as wide whereby a larger portion of the document is unsupported during printing, resulting in very poor contact between the raised printed matter and the paper document.
Also, when it is desired to print "long" lines of printed matter, the diameter of the endorser drum required makes the endorser quite impractical.